186 WARFARE IN THE HUMAN BODY 



times, once when extruded from the Graafian follicle, 

 once when it throws in its lot with the sperm cell and 

 makes common stock of its energy and chromosomatic 

 tools, and again when extruded by the uterus after a 

 prolonged period of parasitism. With a properly and 

 naturally nourished infant the number of births may 

 be said to reach four when it is weaned. Far too much 

 criticism is made of direct adaptation to environment 

 in the adult organism, and far too little study given to 

 pre-embryonic and embryonic stages, even by most of 

 the advocates of such adaptation. 



As mitigating to some extent the fairly obvious 

 biological ignorance of histology, it must be admitted 

 that very little seems known of the histology of the 

 ovaries and the ova, the testes and the spermatoza, for 

 Schafer disposes of the subject in a few lines, and other 

 authorities are equally brief. Something may be found 

 in Wilson, and Weismann himself dealt with it in- 

 effectively. As his theory rendered it unimportant, 

 this is not a matter for wonder. The ovarian tissues 

 and the history of the oocytes seem less known than 

 that of the testes, although in this last case much 

 remains to be cleared up. It is a fact that both sperm cell 

 and ovum develop, not from any more obviously special 

 tissue than epithelium, but very often from epithelioid 

 cells which have not taken on the full character of epi- 

 thelium. To deal first with the testis, we may say with 

 Schafer and Brown, that the sperm cells are developed 

 from the small spermatoblasts which form the inner 

 stratum of the seminal epithelium, and that these them- 

 selves are formed by division from the spermatogenic 

 or mother cell of the second layer. It seems probable 

 that these descend from the lining epithelium. Thus 



